blk_get_aio_context() asserts that blk->ctx is always equal to the root
BDS's context (if there is a root BDS). Therefore,
blk_do_set_aio_context() must update blk->ctx immediately after the root
BDS's context has changed.
Without this patch, the next patch would break iotest 238, because
bdrv_drained_begin() (called by blk_do_set_aio_context()) may then
invoke bdrv_child_get_parent_aio_context() on the root child, i.e.
blk_get_aio_context(). However, by this point, blk->ctx would not have
been updated and thus differ from the root node's context. This patch
fixes that.
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <
20221107151321.211175-3-hreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
return ret;
}
}
+ /*
+ * Make blk->ctx consistent with the root node before we invoke any
+ * other operations like drain that might inquire blk->ctx
+ */
+ blk->ctx = new_context;
if (tgm->throttle_state) {
bdrv_drained_begin(bs);
throttle_group_detach_aio_context(tgm);
}
bdrv_unref(bs);
+ } else {
+ blk->ctx = new_context;
}
- blk->ctx = new_context;
return 0;
}